Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CASH FLOW FROM OPERATING ACTIVITIES
Net income (loss)	$ 99	$ 429	$ (262)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation, depletion and amortization	471	502	544
Net derivative loss (gain) from commodity contracts	59	(1)	90
Net proceeds (payments) on settled commodity derivatives	111	(228)	(7)
Net gain on early extinguishment of debt	(126)	(57)	(4)
Amortization of deferred gain	(70)	(76)	(74)
Gain on asset divestitures	0	(5)	(21)
Other non-cash charges to income, net	131	97	77
Dry hole expenses	7	16	2
Changes in operating assets and liabilities, net:
Decrease (increase) in trade receivables	22	(23)	(45)
(Increase) decrease in inventories	0	(6)	2
Increase in other current assets	(1)	(9)	(2)
Decrease in accounts payable and accrued liabilities	(27)	(178)	(52)
Net cash provided by operating activities	676	461	248
CASH FLOW FROM INVESTING ACTIVITIES
Capital investments	(455)	(690)	(371)
Changes in capital investment accruals	(85)	69	27
Asset divestitures	164	18	33
Acquisitions	(6)	(547)	0
Other	(12)	(6)	(2)
Net cash used in investing activities	(394)	(1,156)	(313)
CASH FLOW FROM FINANCING ACTIVITIES
Proceeds from 2014 Revolving Credit Facility	2,330	2,823	1,696
Repayments of 2014 Revolving Credit Facility	(2,353)	(2,646)	(2,180)
Proceeds from 2017 Term Loan	0	0	1,274
Payments on 2014 Term Loan	0	0	(650)
Debt repurchases	(156)	(199)	(116)
Debt transaction costs	(2)	(4)	(42)
Contributions from noncontrolling interest holders, net	49	796	98
Distributions paid to noncontrolling interest holders	(151)	(121)	(8)
Issuance of common stock	4	54	3
Shares canceled for taxes	(3)	(11)	(2)
Net cash (used) provided by financing activities	(282)	692	73
(Decrease) increase in cash	0	(3)	8
Cash—beginning of year	17	20	12
Cash—end of year	$ 17	$ 17	$ 20